gefran KFM LD, Инструкция по эксплуатации

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4.1.2. Adjusting the belt tension
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2
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Fig. 13
Item Designation Item Designation
1 Driven pulley 4 8 mm deflection
2 V-groove belt 5 80 N test force
3 V-groove washer
Tab. 18 Belt construction
The V-groove belt is to be pretensioned so that with a force of 80N, the deflection of the belt is 8 mm.
If the belt tension is too weak , the belt will slip. This can lead to various faults, such as the driven door not reaching
its end position. See error description in Chap. 5.5 on page 33.
If the belt tension is too taut , premature destruction of the drive shaft bearing may result or the drive shaft
may break after some time. A more precise adjustment of the belt tension is possible by means of resonance
frequency measurement.
See the following description.
4.1.3. Resonance frequency measurement
Using a laptop that is equipped with a simple voice microphone and a program such as "tuner12.exe", the belt
tension can be determined somewhat more precisely.
The measurement program is approx. 290 kB in size and can be downloaded from the Internet at http://www.
techmind.org/audio/tuner12.exe .
4.1.4. Test sequence
• Start the measurement program on the laptop
• Hold the microphone approx. 10 – 20 mm away from the driving belt
•
Pluck the belt (with the drive switched off) to cause it to vibrate (as with the string on a musical instrument)
• Read the vibration value on the laptop display in the left window of the measurement program.
The displayed vibration value should be approx. 180 Hz ± 5%. In the event of deviations, the belt tension is to
be changed accordingly and the test sequence repeated until the desired tension is reached.
The ambient noises in the measuring range should not be excessively loud. The measurement result can be opti-
mised somewhat by adjusting the volume at the microphone input.
Important
Important
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KFM LD • Instruction manual